Heat exchanger tubes can be coiled to permit a substantial length of tubing material to be conveniently disposed within the confines of a heat exchanger housing. When the tubes are used in connection with hot and/or cold fluid, the tubes may have insulation placed on the outer surface thereof.
Tube-in-tube heat exchangers are used in a variety of applications for transferring heat from one fluid to another. Particular configurations of tube-in-tube heat exchangers are described in U.S. Pat. Nos. 5,004,047 and 6,012,514.
Traditionally, tube-in-tube heat exchangers used in geothermal heat pumps employ coiled tube-in-tube heat exchanger tubes. The coiled tubes are wrapped with an insulating material after the tubing is installed. The insulated material is wrapped and taped around an individual tube, or around a coil of tubing material. This process can be time-consuming, and often is performed by a different contractor than the person who installs and/or maintains the heat exchanger.
It would be useful to further improve the effectiveness of insulated heat exchange tube material, as well as the efficiency of installation.